NF2 is a rare genetic condition affecting 1 in 25,000 to 1 in 40,000. Symptoms usually appear during teenage years or later in life and are often life-limiting.
NF2 is a variable condition; there is currently no way of knowing how someone will be affected by NF2. Even within a family, each person will present with different symptoms or features.
Common signs and symptoms
NF2 is usually diagnosed following MRI scans most commonly after presentation to a doctor with symptoms of hearing loss, ringing in the ears (tinnitus) and issues with balance. These symptoms are most commonly the result of benign tumours on the vestibular nerves in the ears. Other benign (and some malignant) tumours may also be found throughout the nervous system, typically in the brain and spine.
Tumours on both hearing nerves (bilateral vestibular schwannomas) are the main criteria for diagnosis. The presence of these tumours distinguish NF2 from NF1 and Schwannomatosis. Alternatively, diagnosis can be made where there is a family history of NF2 along with other nervous system tumours. See Diagnosis for details.
While tumours on the hearing nerves (eighth cranial nerve) are the most common other tumours people with NF2 can develop tumours on other nerves throughout the body as well. The most commonly found tumours are called “schwannomas” because they form on cells that surround the nerves called Schwann cells, which allow the nerves to conduct information around the body. The location of the Schwann cells affected by a tumour will determine the symptoms that will arise.
There are several symptoms to be aware of and watch for in someone affected by NF2. These include:
- Sudden changes to hearing
- Changes in vision
- Sudden, severe headaches
- Unexplained drowsiness
- Loss of sensation, tingling or weakness in an arm or leg
- Development of pain
- Dizziness, unsteadiness or difficulties with balance
- Unexplained drowsiness
NF2 is very different to NF1 in that people with NF2 do not usually have a large number of skin changes as seen in NF1, and most people with the condition will need operations or other treatments for brain or spinal cord tumours at some time.
What is the cause of NF2?
The condition is caused by a change in the spelling of a gene on chromosome 22. While NF1 and NF2 are caused by different changes in spelling of two different genes, they are similar in that they can both be either inherited from a parent or start with no previous family history. Each time a person with NF2 has a child, that child has a 1 in 2 (or 50%) chance of inheriting the condition.
Some people may also be given a diagnosis of mosaic (or segmental) NF2. This occurs when only one part of the body is affected by the condition. Please visit Genetics to find out more.
For information sheets relating to NF2 please go to Factsheets.